1. Field of the Invention
The invention relates to a stamping tool, in particular a cutting rule, formed from a thermally treated and/or quenched and tempered steel strip, shaped on the narrow sides with, on the one hand, a cutting part with a cutting edge and, on the other hand, with a back part.
2. Discussion of Background Information
Stamping tools, in particular cutting rules, are used to divide or perforate flat materials, such as paper, cardboard, plastic films and the like in flatbed stamping machines and/or in rotational stamping machines.
The problems of producing a desired cut and a proposed solution are disclosed by WO 2009/121383. It is proposed in this document to provide projections on the back of the cutting rule, which projections can be plastically deformed during the first use of the tool and in this manner automatically cause an optionally necessary local or regional height leveling of the cutting rules in the carrier plate between the stamping plate and the upper plate of the stamping machine, a so-called leveling of the tool.
The projections on the back of the cutting rule are produced by a precise chip-removing routing of the spaces, for example, by grinding, milling and the like.
Furthermore, it is proposed in the above document to provide a surface decarburization in the back region of the cutting rule in order to achieve a facilitation of the plastic deformation of the projections with an automatic leveling during the first use.
According to reports, elevations were produced experimentally on the back of cutting rules by the application of foreign material, which elevations are designed to cause a leveling of the tool by means of deformation during a first cutting load.
The above-mentioned measures and embodiments of the back parts of cutting rules can definitely render possible an automatic leveling of the same during a first cutting load, but have in common the disadvantage of a complex production of the recesses in the contour and the problem of a deformation path that can be adjusted in a targeted manner, depending on a local stress of the back part of the cutting rule for an automatic leveling in the stamping machine that preserves the tool and the plates. Furthermore, the operator of stamping machines requires an increase in tool life and an avoidance of fatigue fractures of the cutting rules.